This change replaces the ENGINE's underlying mechanics with the new

ENGINE_TABLE-based stuff - as described in crypto/engine/README.

Associated miscellaneous changes;
 - the previous cipher/digest hooks that hardwired directly to EVP's
   OBJ_NAME-based storage have been backed out. New cipher/digest support
   has been constructed and will be committed shortly.
 - each implementation defines its own ENGINE_load_<name> function now.
 - the "openssl" ENGINE isn't needed or loaded any more.
 - core (not algorithm or class specific) ENGINE code has been split into
   multiple files to increase readability and decrease linker bloat.
 - ENGINE_cpy() has been removed as it wasn't really a good idea in the
   first place and now, because of registration issues, can't be
   meaningfully defined any more.
 - BN_MOD_EXP[_CRT] support is removed as per the README.
 - a bug in enginetest.c has been fixed.

NB: This commit almost certainly breaks compilation until subsequent
changes are committed.

1 files changed, 361 insertions, 0 deletions

diff --git a/crypto/engine/eng_table.c b/crypto/engine/eng_table.c
new file mode 100644
index 0000000000..4192144565
--- /dev/null
+++ b/crypto/engine/eng_table.c
@@ -0,0 +1,361 @@
+/* ====================================================================
+ * Copyright (c) 2000 The OpenSSL Project.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer. 
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ *    software must display the following acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission. For written permission, please contact
+ *    licensing@OpenSSL.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ *    nor may "OpenSSL" appear in their names without prior written
+ *    permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com).  This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ *
+ */
+
+#include <openssl/evp.h>
+#include <openssl/engine.h>
+#include "eng_int.h"
+
+/* This is the type of item in the 'implementation' table. Each 'nid' hashes to
+ * a (potentially NULL) ENGINE_PILE structure which contains a stack of ENGINE*
+ * pointers. These pointers aren't references, because they're inserted and
+ * removed during ENGINE creation and ENGINE destruction. They point to ENGINEs
+ * that *exist* (ie. have a structural reference count greater than zero) rather
+ * than ENGINEs that are *functional*. Each pointer in those stacks are to
+ * ENGINEs that implements the algorithm corresponding to each 'nid'. */
+
+/* The type of the items in the table */
+typedef struct st_engine_pile
+	{
+	/* The 'nid' of the algorithm/mode this ENGINE_PILE structure represents
+	 * */
+	int nid;
+	/* A stack of ENGINE pointers for ENGINEs that support this
+	 * algorithm/mode. In the event that 'funct' is NULL, the first entry in
+	 * this stack that initialises will be set as 'funct' and assumed as the
+	 * default for operations of this type. */
+	STACK_OF(ENGINE) *sk;
+	/* The default ENGINE to perform this algorithm/mode. */
+	ENGINE *funct;
+	/* This value optimises engine_table_select(). If it is called it sets
+	 * this value to 1. Any changes to this ENGINE_PILE resets it to zero.
+	 * As such, no ENGINE_init() thrashing is done unless ENGINEs
+	 * continually register (and/or unregister). */
+	int uptodate;
+	} ENGINE_PILE;
+
+/* The type of the hash table of ENGINE_PILE structures such that each are
+ * unique and keyed by the 'nid' value. */
+struct st_engine_table
+	{
+	LHASH piles;
+	}; /* ENGINE_TABLE */
+
+/* This value stores global options controlling behaviour of (mostly) the
+ * engine_table_select() function. It's a bitmask of flag values of the form
+ * ENGINE_TABLE_FLAG_*** (as defined in engine.h) and is controlled by the
+ * ENGINE_[get|set]_table_flags() function. */
+static unsigned int table_flags = 0;
+
+/* API function manipulating 'table_flags' */
+unsigned int ENGINE_get_table_flags(void)
+	{
+	return table_flags;
+	}
+void ENGINE_set_table_flags(unsigned int flags)
+	{
+	table_flags = flags;
+	}
+
+/* Internal functions for the "piles" hash table */
+static unsigned long engine_pile_hash(const ENGINE_PILE *c)
+	{
+	return c->nid;
+	}
+static int engine_pile_cmp(const ENGINE_PILE *a, const ENGINE_PILE *b)
+	{
+	return a->nid - b->nid;
+	}
+static IMPLEMENT_LHASH_HASH_FN(engine_pile_hash, const ENGINE_PILE *)
+static IMPLEMENT_LHASH_COMP_FN(engine_pile_cmp, const ENGINE_PILE *)
+static int int_table_check(ENGINE_TABLE **t, int create)
+	{
+	LHASH *lh;
+	if(*t)
+		return 1;
+	if(!create)
+		return 0;
+	if((lh = lh_new(LHASH_HASH_FN(engine_pile_hash),
+			LHASH_COMP_FN(engine_pile_cmp))) == NULL)
+		return 0;
+	*t = (ENGINE_TABLE *)lh;
+	return 1;
+	}
+
+/* Privately exposed (via eng_int.h) functions for adding and/or removing
+ * ENGINEs from the implementation table */
+int engine_table_register(ENGINE_TABLE **table, ENGINE_CLEANUP_CB cleanup,
+		ENGINE *e, const int *nids, int num_nids, int setdefault)
+	{
+	int ret = 0, added = 0;
+	ENGINE_PILE tmplate, *fnd;
+	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
+	if(!(*table))
+		added = 1;
+	if(!int_table_check(table, 1))
+		goto end;
+	if(added)
+		/* The cleanup callback needs to be added */
+		engine_cleanup_add_first(cleanup);
+	while(num_nids--)
+		{
+		tmplate.nid = *nids;
+		fnd = lh_retrieve(&(*table)->piles, &tmplate);
+		if(!fnd)
+			{
+			fnd = OPENSSL_malloc(sizeof(ENGINE_PILE));
+			if(!fnd)
+				goto end;
+			fnd->uptodate = 1;
+			fnd->nid = *nids;
+			fnd->sk = sk_ENGINE_new_null();
+			if(!fnd->sk)
+				{
+				OPENSSL_free(fnd);
+				goto end;
+				}
+			fnd->funct= NULL;
+			lh_insert(&(*table)->piles, fnd);
+			}
+		/* A registration shouldn't add duplciate entries */
+		sk_ENGINE_delete_ptr(fnd->sk, e);
+		/* if 'setdefault', this ENGINE goes to the head of the list */
+		if(!sk_ENGINE_push(fnd->sk, e))
+			goto end;
+		/* "touch" this ENGINE_PILE */
+		fnd->uptodate = 0;
+		if(setdefault)
+			{
+			if(!engine_unlocked_init(e))
+				{
+				ENGINEerr(ENGINE_F_ENGINE_TABLE_REGISTER,
+						ENGINE_R_INIT_FAILED);
+				goto end;
+				}
+			if(fnd->funct)
+				engine_unlocked_finish(fnd->funct, 0);
+			fnd->funct = e;
+			}
+		nids++;
+		}
+	ret = 1;
+end:
+	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
+	return ret;
+	}
+static void int_unregister_cb(ENGINE_PILE *pile, ENGINE *e)
+	{
+	int n;
+	/* Iterate the 'c->sk' stack removing any occurance of 'e' */
+	while((n = sk_ENGINE_find(pile->sk, e)) >= 0)
+		{
+		sk_ENGINE_delete(pile->sk, n);
+		/* "touch" this ENGINE_CIPHER */
+		pile->uptodate = 0;
+		}
+	if(pile->funct == e)
+		{
+		engine_unlocked_finish(e, 0);
+		pile->funct = NULL;
+		}
+	}
+static IMPLEMENT_LHASH_DOALL_ARG_FN(int_unregister_cb,ENGINE_PILE *,ENGINE *)
+void engine_table_unregister(ENGINE_TABLE **table, ENGINE *e)
+	{
+	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
+	if(int_table_check(table, 0))
+		lh_doall_arg(&(*table)->piles,
+			LHASH_DOALL_ARG_FN(int_unregister_cb), e);
+	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
+	}
+
+static void int_cleanup_cb(ENGINE_PILE *p)
+	{
+	sk_ENGINE_free(p->sk);
+	if(p->funct)
+		engine_unlocked_finish(p->funct, 0);
+	OPENSSL_free(p);
+	}
+static IMPLEMENT_LHASH_DOALL_FN(int_cleanup_cb,ENGINE_PILE *)
+void engine_table_cleanup(ENGINE_TABLE **table)
+	{
+	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
+	if(*table)
+		{
+		lh_doall(&(*table)->piles, LHASH_DOALL_FN(int_cleanup_cb));
+		lh_free(&(*table)->piles);
+		*table = NULL;
+		}
+	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
+	}
+
+/* Exposed API function to get a functional reference from the implementation
+ * table (ie. try to get a functional reference from the tabled structural
+ * references) for a given cipher 'nid' */
+#ifndef ENGINE_TABLE_DEBUG
+ENGINE *engine_table_select(ENGINE_TABLE **table, int nid)
+#else
+ENGINE *engine_table_select_tmp(ENGINE_TABLE **table, int nid, const char *f, int l)
+#endif
+	{
+	ENGINE *ret = NULL;
+	ENGINE_PILE tmplate, *fnd;
+	int initres, loop = 0;
+
+	/* If 'engine_ciphers' is NULL, then it's absolutely *sure* that no
+	 * ENGINEs have registered any implementations! */
+	if(!(*table))
+		{
+#ifdef ENGINE_TABLE_DEBUG
+		fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, no "
+			"registered for anything!\n", f, l, nid);
+#endif
+		return NULL;
+		}
+	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
+	/* Check again inside the lock otherwise we could race against cleanup
+	 * operations. But don't worry about a fprintf(stderr). */
+	if(!int_table_check(table, 0))
+		goto end;
+	tmplate.nid = nid;
+	fnd = lh_retrieve(&(*table)->piles, &tmplate);
+	if(!fnd)
+		goto end;
+	if(fnd->funct && engine_unlocked_init(fnd->funct))
+		{
+#ifdef ENGINE_TABLE_DEBUG
+		fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using "
+			"ENGINE '%s' cached\n", f, l, nid, fnd->funct->id);
+#endif
+		ret = fnd->funct;
+		goto end;
+		}
+	if(fnd->uptodate)
+		{
+		ret = fnd->funct;
+		goto end;
+		}
+trynext:
+	ret = sk_ENGINE_value(fnd->sk, loop++);
+	if(!ret)
+		{
+#ifdef ENGINE_TABLE_DEBUG
+		fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, no "
+				"registered implementations would initialise\n",
+				f, l, nid);
+#endif
+		goto end;
+		}
+#if 0
+	/* Don't need to get a reference if we hold the lock. If the locking has
+	 * to change in future, that would be different ... */
+	ret->struct_ref++; engine_ref_debug(ret, 0, 1)
+#endif
+	/* Try and initialise the ENGINE if it's already functional *or* if the
+	 * ENGINE_TABLE_FLAG_NOINIT flag is not set. */
+	if((ret->funct_ref > 0) || !(table_flags & ENGINE_TABLE_FLAG_NOINIT))
+		initres = engine_unlocked_init(ret);
+	else
+		initres = 0;
+#if 0
+	/* Release the structural reference */
+	ret->struct_ref--; engine_ref_debug(ret, 0, -1);
+#endif
+	if(initres)
+		{
+		/* If we didn't have a default (functional reference) for this
+		 * 'nid' (or we had one but for whatever reason we're now
+		 * initialising a different one), use this opportunity to set
+		 * 'funct'. */
+		if((fnd->funct != ret) && engine_unlocked_init(ret))
+			{
+			/* If there was a previous default we release it. */
+			if(fnd->funct)
+				engine_unlocked_finish(fnd->funct, 0);
+			/* We got an extra functional reference for the
+			 * per-'nid' default */
+			fnd->funct = ret;
+#ifdef ENGINE_TABLE_DEBUG
+			fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, "
+				"setting default to '%s'\n", f, l, nid, ret->id);
+#endif
+			}
+#ifdef ENGINE_TABLE_DEBUG
+		fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using "
+				"newly initialised '%s'\n", f, l, nid, ret->id);
+#endif
+		goto end;
+		}
+	goto trynext;
+end:
+	/* Whatever happened - we should "untouch" our uptodate file seeing as
+	 * we have tried our best to find a functional reference for 'nid'. If
+	 * it failed, it is unlikely to succeed again until some future
+	 * registrations (or unregistrations) have taken place that affect that
+	 * 'nid'. */
+	if(fnd)
+		fnd->uptodate = 1;
+#ifdef ENGINE_TABLE_DEBUG
+	if(ret)
+		fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching "
+				"ENGINE '%s'\n", f, l, nid, ret->id);
+	else
+		fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching "
+				"'no matching ENGINE'\n", f, l, nid);
+#endif
+	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
+	/* Whatever happened, any failed init()s are not failures in this
+	 * context, so clear our error state. */
+	ERR_clear_error();
+	return ret;
+	}